This publication discusses what a perm rating is, the effect of material thickness on a perm rating, vapor barriers in the Alaska environment, when to trust perm ratings, and provides perm ratings for various materials and thicknesses of those materials.

This item was harvested from the University of Alaska Fairbanks, Cooperative Extension Service web site: http://www.uaf.edu/ces/publications/freepubs/EEM-00259.pdf in March 2007 for the Alaska State Publications Program; remote access available via StaticURL.

Abstract:

This publication discusses what a perm rating is, the effect of material thickness on a perm rating, vapor barriers in the Alaska environment, when to trust perm ratings, and provides perm ratings for various materials and thicknesses of those materials.

Permeability of common building material to water vapor/Richard D Seifert; University of Alaska Fairbanks. Cooperative Extension Service.; [Fairbanks] : University of Alaska Fairbanks, Cooperative Extension Service, [2006]